To study spatial variation of the atmospheric boundary with respect to variations of surface temperature and wave state in the coastal zone, the NOAA LongEZ aircraft flew over the shoaling zone off the coast of North Carolina. Repeated flights were conducted between the coast line at Duck, NC, and 90 Km offshore. In addition, many repeated runs parellel to the coast line were made at several off-shore distances. These data are used to study spatial variation of air-sea interaction. With offshore flow, the internal boundary layer in the coastal zone may be strongly stable or unstable and vary dramatically in the downstream distance, in contrast to normal open ocean conditions.
While the influence of developing wave state and shoaling of onshore swell is significant, the flow appears to be more strongly affected by advection, local pressure fields due to differential heating between land and sea and spatial variation of sea surface temperature. In some cases, elevated shear generation of turbulence leads to complicated vertical structure. This elevated shear appears to
be related to local mesoscale flows.